嗜酸乳杆菌SR-1产类细菌素发酵条件及生物学特性的研究

Fermentation conditions and biological characteristics of bacteriocin secreted by a strain of Lactobacillus acidophilus

本研究通过正交试验获得嗜酸乳杆菌SR-1分泌类细菌素的最适培养条件,即葡萄搪2%,大豆蛋白胨2.5%,酵母粉0.4%,血浆蛋白2.5%。并首次利用流加培养的方式,改进了类细菌素产生菌的发酵条件,抑菌直径从19 mm提高到25 mm,同时对类细菌素生物学特性进行了初步的探索。结果表明:嗜酸乳杆菌产生的类细菌素对多种蛋白酶不敏感,在低pH下能抑制革兰阴性、阳性的致病菌,在pH 6.5下吸附菌体作用最强。

The optimum fermentation conditions of Lactobacillus acidophilns secreting bacteriocin had been achieved through orthogonal test in this study,and its components includes 2.0% of glucose,2.5% of soya peptone,0.4% of yeast extract,and 2.5% of plasma protein. The fed-batch culture had been used to improve the fermentation conditions of Lactobacillus acidophilus and bacterial inhibition diameters had significantly increased from 19 mm to 25 mm. Furthermore, the biological characteristics of bacteriocin had been preliminarily explored. The results indicated that the bacteriocin secreted by Lactobacillus acidophilus was insensitive to many proteinases and could inhibit gram-negative and gram-positive bacteria under low pH condition. It possesses higher absorption to bacteria under pH6.5.